I've been reading most of the posts on engine overheating issues and most problems are unique to themselves. Hence why I am posting my problems / experiences with the hopes someone can offer me some advice.

My car is a 2003 w/63k miles, and recently the car began running hot on the way home. As I was on the hwy the temp began increasing soon followed by "reduced power" warnings. I pulled the car over every time the temperature increased to less then comfortable levels and I let it cool down for 20 minutes in between attempts to get home. After 2 intervals of heating up and cooling down the third start-up-and-go worked like a charm. I made it home with no problems whatsoever. That next morning after reading some posts I decided to replace the thermostat with a stock OEM replacement part and that went in without a hitch, However the vehicle still ran extremely hot.

I returned to the posts and then followed the instructions about "burping" the coolant. My steps were simple
1. I removed the coolant cap.
2. Topped it off with coolant/water
3. Started the engine
4. Turned on the windshield defogger on HOT
5. Sat back and watched the bubbles form at the mouth of the coolant reservoir.

Now here's what I observed:

* The coolant level never really substantially decreased (only by what ever spilled over with the bubbles)
* The defogger never got warm
* The coolant began bubbling as if it were boiling over. (It was warm to the touch)
* The temperature of the engine once again increased to the levels where you know it was about to overheat, so it was promptly shut down.
* The hose coming from the thermostat never got hot and the pressure was at a minimum.
* The hoses from the reservoir did get hot to the touch and contained obvious pressure within them.

If anyone can offer suggestions based on these experiences it would be greatly appreciated.

Nick

 

did you test to see if the " new" thermostat was indeed opening??? there have been many " new" thermostats who failed this test. That's where I would start. it's very simple... the pump, pumps the coolant around the system, if the pump is pumping and the stat is open , circulation occurs... ON a side note... I took my radiator out of the car the other day.... this was after I cleaned it.. I cleaned like Ive done every year for the last ten years.. it visually looked clean when it was In the car... Once I took it out, and looked through the cooling fins, there was still plenty of debris stuck in there.. I did not take any photos,, but.. I now know that when I clean my radiator , I will take it out.,,, it will also give me an opportunity to clean the ac condenser much better... removing the radiator takes about 30 minutes. Now My ac is frigid cold an my coolant act like its suppose too.

 

Thanks for your reply.

How do I check if circulation is occurring? How do I confirm the pump is doing it's job?

Thank you.

 

My bet is you have trash,dirt, sand un the AC condensor and between the rediator and condensor on in the front where the air enters the condensor/radiator. VERY COMMON problem.

Go that route FIRST. Its the easiest and most rewarding.. Remove the air bridge and then the plastic cover over the radiator/condensor. If you see lots of debri,,,, GET CLEANING!

 

Will do, I'll post results tomorrow.

Thank you

 

>The temperature of the engine once again increased to the levels where you know it was about to overheat, so it was promptly shut down.<

How hot is the car getting? Temps?

 

Without looking at a gauge right this minute I can say I've shut it down at approx 250 degrees after only a short while of idling. It achieved that temp without depressing the accelerator once. I wasn't time keeping but I can say it took around 10 minutes to get to that temp.

 

I went through the same ordeal (not quite 250 but 240 on the road) a couple of years ago. After cleaning, checking for bubbles, the cap, thermostat etc. it turned out the water pump was shot.

 

how much does it cost to replace the waterpump? (professionally installed, not everyone's a mechanic!)

 

I'm curious too!

 

Well, you're going to be at the mercy of the local shops. Figure 2-3 hrs. labor @ $85 per or so.

Here's a thread from C5 Gen - http://forums.corvetteforum.com/c5-g...r-changed.html

You can search for a step by step.

 

sounds to me like you have a bad Tstat combined
with air still in the system.
IF your heat/defrost doesnt get hot, then that's a sure sign
of air pockets in coolant.
Run that thing in driveway with cap off again till temp gets
up to 220 or so. Make sure your fans kick in about then too.
Run the heater on hot/ medium fan setting the entire time.

Then just turn it off and let cool for a couple hours. Repeat warm up.
Let cool. Top coolant. Put cap on. Run again til warm
Verify you have heat in pass compartment. If so , then take out for a drive.